Safety tubing lock



Sept. 15, 1931. D. BROOKSHIRE 1,823,186

I S-AFEI'Y TUBING LOCK I Filed Sept. 6, 1929 Patented Sept. 15, 1931 DRAKE BROOKSHIRE, OF ,GALENA, KANSAS SAFETY TUBING LOCK Application filed September This invention relates to a safety tubing lock particularly adapted for use in connection with deep oil wells or similar excavations for automatically attaching the tubing to the well casing to prevent loss of the tub ing in case of breakage of the tubing from its support orwhen it is desired to stop the descent of the tubing into the well. V

An object of this inventionis to provide a safety tubing lock which will be positive in its action and which will quickly and securely hold the tubing in case of accident or which may be forced to operate to prevent further descent of the tubing when it is desired to stop the lowering of the tubing into the well. Another object is to provide a device of the character referred to having an expansible member mounted on the tubing and capable of relative movement with respect thereto, a second relatively movable member being slidably mounted on the tubing and bein adapted to expand the expansible mem er under certain conditions.

A further object is to provide a device of the character referred to wherein a floater other similar means is connected with the expansible member and movable therewith to positively cause differential movement between the tubing and the expansible member whereby the slidable expanding means on the tubing will be enabled to expand the expansible member. 1

A further object is to provide adevice of the character referred to wherein the tub: ing is provided with means to strike a blow upon the upper surface of the slidable expanding means to force the latteninto positive engagement with the expanslble member.

Other objects and advantages of the invention will become ap arent during the course of the following escription.

In the drawings I have shown one embodt ment of my invention. In this showing,

Figure 1 is a front elevation of the device arranged in a section of well casing,

Figure 2 is an enlarged vertical sectional view, 7

Figure 3 is a transverse sectional view 6, 1929. Serial No. 390,837.

taken substantially on line 3'3 of Figure 2, and

Figure 4 is a perspective view of the expanding means. 7 7 Referring to the drawings the numeral 10 indicates a section of well casing or other tubular member into which it is desired to lower a string of tubing or the like, as will be understood; Thenum eral 11 indicates an upper section of well tubing joined toa short length of well tubing 12 by means of an internally threaded coupling 13. The ends of the sections of well tubing are threaded substan tially as shown at 14 to be received in the coupling 13 and the latter is provided with 5 a substantially OvaLshaped upper surface, as 2 indicated at 15. Beneath the section 12 of the-well tubingis a lower section of tubing16'. As shown, the adjacent extremities of these sections of tubings are threaded as shownat 17 and an internally threaded couplinglt? is adapted'to' secure the sections of tubing together. i

A substantially annular inverted cupshaped member 19 is slidab'ly mounted on the section of tubing 11 and its inner surface snugly engagesthe outer surface of the coupling 13 when the device is in theposition shown in Figure 2. The lower portion of the member 19- has secured thereto the upper so ends of a plurality of sw'ingable' arms 20 and the lower extremities of these arms are suitably secured to an expansible member The member 21 is preferably formed of a pair of complementary sections 22 23 spaced to provide openings 24 between the complementary members in their normal inoperative position. Each complementary member is provided with a: plurality of gripping teeth 25 arranged circu-mferentiall y, the purpose of which will become apparent. The diameter o-f-theexpansibl'emember 21 is slightly less than theinside diameter of the well casing.

Adjacent its upper extremity the member, 19 is internally threaded as at 26 and receives the externally threaded extremity 27 of a float 28 or other similar member. As shown, the float 28 is preferably formed with a hollow cylindricalbody 29 provided with closure members 30 adjacent each extremity of the body. Each closure member has a relatively long neck 31 extending longitudinally of the tubing. It will be apparent that the member 19, the expansible member 21 and the float 28 are movable together and independently of the tubing.

Slidably mounted on the section of tubing 12 is a tapered expanding member or wedge 32 adapted to expand the expansible member 21 under certain conditions.

The operation of the. device is as follows:

l Vell tubing equipped with the safety lock described is lowered into the well casing in the usual manner. During normal descent of the tubing the parts of the locking means will remain in their inoperative position shown in Figure 2. However, if the tubing should break above the locking device the tubing will immediately begin to descend at a greater rate of speed than it attains by being mechanically lowered. The inertia of the tubing will therefore tend to permit the tubing to drop more rapidly than the locking device. This differential movement between the tubing and the locking device will, if the drop is or" sufficient length, eventually cause the wedge 32 to expand the complementary members and cause the teeth of the latter to grip the interior of the well casing to prevent further descent of the tubing. In order to insure that the differential movement between the locking means and the tubing is suflicient to quickly cause the locking means to function, I have provided the fioat 28, or other equivalent means.

The float 28 is connected with the expansible member 21 and when the tubing begins to descend more rapidly than normal, the float serves to immediately check the increased downward movement of the expansible member. This downward movement of the expansible member is not stopped entirely by the float, but the latter quickly causes a substantial differential movement between the expansible member and the tubing, thus enabling the expanding means or wedge 32 to quickly engage the expansible member and force the teeth of the latter into engagement with the well casing.

In order to further insure quick and positive locking action of the expansible member, I have slidably mounted the wedge 32 on the tubing and the lower surface of the coupling 13 will strike a hard blow on the upper surface of the wedge thus forcing the latter into engagement with the expansiblemember.

Ifit is desired to stop the tubing during its normal descent and at the same time relieve the strain on the lowering mechanism, the tubing may be permitted to suddenly drop at increased speed for a short distance and the locking device will operate, as will be apparent.

In order to unlock the device it is only necessary to pull the tubing upwardly and the coupling 18 will force the wedge 32 out of engagement with the expansible member.

It is to be understood that the form of my invention herewith shown and described is to be taken as a preferred example of the same and that various changes in the shape, size, and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subj oined claims.

I claim: v

1. A tubing lock comprising an expansible member mounted for independent move ment on the tubing, means slidable on the tubing for expanding said member, means on the tubing for supporting the expansible member in inoperative position, said last named means being operable upon diflterem tial movement of the tubing and the expansible member to engage said expanding means to force the latter to expand said expansible member. I

2. A tubing lock comprising an expansible member mounted for independent movement on the tubing, means slidable on the tubing for expanding said member, means on the tubing for supporting the expansible member in inoperative position, and means for causing differential movement of said tubing and said expansible member, said supential movement of the tubing and the expansible member to strike said expanding means a sharp blow to force the latter to expand said expansible member.

3. A tubing lock comprising an expansible member mounted for independent movement on the tubing, means 'for expanding said member also mounted for independent movement on the tubing, means on the tubing for supporting the expansible member in inoperative position, and means connected to said expansible member to cause differential movement between the latter and said tubing, said supporting means being operable upon differential movement of the tubing and the expansible member to engage said expanding means to force the latter to expand said expansible member.

'4. A tubing lock comprising an expansible member mounted for independent movement on the tubing, means slidable on the tubing for expanding said member, a float slidable on the tubing and being movable with and connected to said expansible member, means on the tubing for supporting the expansible member ininoperative position, said last named means being operable upon differential movement of the tubing and the expansible member to strike said expanding means a sharp blow to force the latter to expand said expansible member. i

5. A tubing lock comprising a substantially hollow expansible member mounted for independent movement on the tubing, a

'95 porting means being operable upon difiertapered member slidably mounted on said tubing above said expansible member and adapted to expand the latter, a float slidable on the tubing above said expansible member, connections between said float and said expansible member whereby the latter and the float will move as a unit, said float being adapted to cause difierential movement of the tubing and the expansible member, means on the tubing for supporting the expansible member in inoperative position, said last named means being operable upon diflerential movement of the tubing and the expansible member to engage said tapered member to force the latter to expand said expansible member.

In testimony whereof I aflix my signature.

DRAKE BROOKSHIRE. 

